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  <title>Boost Offset Separator</title>
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  <p><img src="../../../boost.png" alt="C++ Boost" width="277" height=
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  <h1 align="center">Offset Separator</h1>
  <pre>
class offset_separator
</pre>

  <p>The <tt>offset_separator</tt> class is an implementation of the <a href=
  "tokenizerfunction.htm">TokenizerFunction</a> concept that can be used with
  the <a href="tokenizer.htm">tokenizer</a> class to break text up into
  tokens. The <tt>offset_separator</tt> breaks a sequence of <tt>Char</tt>'s
  into strings based on a sequence of offsets. For example, if you had the
  string "12252001" and offsets (2,2,4) it would break the string into 12 25
  2001. Here is an example.</p>

  <h2>Example</h2>
  <pre>
// simple_example_3.cpp
#include&lt;iostream&gt;
#include&lt;boost/tokenizer.hpp&gt;
#include&lt;string&gt;

int main(){
   using namespace std;
   using namespace boost;
   string s = "12252001";
   int offsets[] = {2,2,4};
   offset_separator f(offsets, offsets+3);
   tokenizer&lt;offset_separator&gt; tok(s,f);
   for(tokenizer&lt;offset_separator&gt;::iterator beg=tok.begin(); beg!=tok.end();++beg){
     cout &lt;&lt; *beg &lt;&lt; "\n";
   }
}
</pre>

  <p>&nbsp;</p>

  <h2>Construction and Usage</h2>

  <p>The offset_separator has 1 constructor of interest. (The default
  constructor is just there to make some compilers happy). The declaration is
  below</p>
  <pre>
template&lt;typename Iter&gt;
offset_separator(Iter begin,Iter end,bool bwrapoffsets = true, bool breturnpartiallast = true)
</pre>

  <table border="1" summary="">
    <tr>
      <td>
        <p align="center"><strong>Parameter</strong></p>
      </td>

      <td>
        <p align="center"><strong>Description</strong></p>
      </td>
    </tr>

    <tr>
      <td>begin, end</td>

      <td>Specify the sequence of integer offsets.</td>
    </tr>

    <tr>
      <td>bwrapoffsets</td>

      <td>Tells whether to wrap around to the beginning of the offsets when
      the all the offsets have been used. For example the string
      "1225200101012002" with offsets (2,2,4) with bwrapoffsets to true,
      would parse to 12 25 2001 01 01 2002. With bwrapoffsets to false, it
      would parse to 12 25 2001 and then stop because all the offsets have
      been used.</td>
    </tr>

    <tr>
      <td>breturnpartiallast</td>

      <td>Tells whether, when the parsed sequence terminates before yielding
      the number of characters in the current offset, to create a token with
      what was parsed, or to ignore it. For example the string "122501" with
      offsets (2,2,4) with breturnpartiallast set to true will parse to 12 25
      01. With it set to false, it will parse to 12 25 and then will stop
      because there are only 2 characters left in the sequence instead of the
      4 that should have been there.</td>
    </tr>
  </table>

  <p>To use this class, pass an object of it anywhere a TokenizerFunction is
  required. If you default constructruct the object, it will just return
  every character in the parsed sequence as a token. (ie it defaults to an
  offset of 1, and bwrapoffsets is true).</p>

  <p>&nbsp;</p>

  <h2>Model of</h2>

  <p><a href="tokenizerfunction.htm">TokenizerFunction</a></p>
  <hr>

  <p><a href="http://validator.w3.org/check?uri=referer"><img border="0" src=
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  <p>Revised 
  <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->25
  December, 2006<!--webbot bot="Timestamp" endspan i-checksum="38518" --></p>

  <p><i>Copyright &copy; 2001 John R. Bandela</i></p>

  <p><i>Distributed under the Boost Software License, Version 1.0. (See
  accompanying file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  copy at <a href=
  "http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>)</i></p>
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